1. Field of the Invention
The present invention broadly concerns a mask which is to be worn in conditions of fire and smoke to filter harmful particulates and gases. More particularly, it is concerned with a mask which includes a lightweight and disposable filter element which includes a carrier element and a coating of aloe gel for removing smoke particulates and toxic gas during breathing to permit temporary work and escape.
2. Description of the Prior Art
The danger to persons attendant to fire has long been recognized to include death and injury attributable to smoke inhalation. In addition to injuries attributable to burns, one of the major causes of death and injury during fire is smoke inhalation. In many fire and smoke environments, there is sufficient oxygen available to permit escape, but the individual is overcome by smoke inhalation or toxic gas. Devices which are directed to filtering smoke particulates include U.S. Pat. Nos. 4,402,317 and 4,854,314. While the devices shown therein are useful in filtering smoke particulates during escape of occupants from a structure, they do not address the need for uses in other applications nor for the filtering of toxic gases such as hydrogen cyanide generated during building fires.
Firefighters also need temporary protection from smoke and fire. Firefighters, and especially those encountering brush fires and forest fires, may need to carry a substantial amount of equipment which may not include respirators. They may also suddenly encounter a dangerous situation such as the reversal of direction of a fire which may expose them to unexpected smoke and fire hazards. While masks have been developed for use in these environments, such as shown in U.S. Pat. No. 5,628,308, they have been uncomfortable to wear and expensive. Moreover, they have failed to address the need for a lightweight, temporary filter to remove toxic gas such as hydrogen cyanide from the air breathed by the wearer.
As a result, there has developed a need for a lightweight, easily storable filter mask which, in various constructions, can be stored in a home or office for emergency use, or used by firefighters or in industrial applications to augment available respirators.
The present invention satisfies the need for a lightweight, portable, and inexpensive mask capable of filtering both smoke particulates and hazardous chemicals which can be adapted to different needs. In its simplest form, the present invention includes a filter element and a retainer. The filter element has a container having a permeable fabric cover and a filling of shiftable bodies covered with a coating including a quantity of aloe vera gel. The retainer includes a support strap connected to the cover. Surprisingly, the coating primarily of aloe vera gel having an elevated pH as used in the present invention is not only non-toxic and gentle to the wearer if it contacts the skin, but traps smoke particulates and neutralizes toxic gases which would be harmful to the wearer. The aloe vera gel is preferably combined with a base to elevate the pH of the coating to an alkaline pH level of about 9.25 to 10. As a result, a high degree of neutralization of toxic gases such as hydrogen cyanide which come in contact with the aloe vera gel. The beads are preferably of a lightweight, non-absorbent material such as polystyrene of mixed sizes in the range of 0.01 inch to 0.5 inch in diameter. The simple filter mask described above may be worn to aid in the removal of smoke particulates and toxic gases during the escape of individuals from homes and other buildings in which smoke and fire is encountered.
In a second embodiment, the basic filter element, as described above without the strap, is provided as a disposable element within a retainer or mask. The filter element is removably attached to the inside of the facial portion of the mask to be in direct contact with and conform around the nose and mouth of the wearer, thus causing the inhaled air to be drawn therethrough and filtered. The facial portion of the retainer mask preferably has an outer, fire resistant fabric layer and includes a pocket for receiving the filter element therein, and straps for holding the facial portion in place. The retainer mask may also include a collar portion which is attached to a lower edge of the facial portion and hang downwardly therefrom to protect the neck and upper chest area of the wearer from heat and sparks. Additionally, the facial portion may be provided with an attachment member, such as a snap or hook and loop fastener, to connect to a firefighters goggles to provide additional resistance to slippage of the filter element away from the nose and mouth of the wearer.
In a third embodiment of the mask of the present invention, the filter element as described with reference to the second embodiment is attached to the inside of a retainer including shell which includes a substantially impermeable barrier except for at least one-way valve and an inlet for ensuring air entering the shell passes through the filter element. Straps are connected to the shell for holding it in place on the face of the wearer. The one-way valve is preferably an exhalation-only valve, with the filter element covering the inside of the inlet.
A fourth embodiment of the present invention is similar to the third embodiment, but wherein the filter element is provided as an external component to the mask. The filter element then preferably includes a rigid or semi-rigid container carrying the filling, which may be further augmented by carbon monoxide handling material. The bodies are covered with the modified aloe vera gel as described above either before insertion into the container or preferably thereafter, whereby the uncoated bodies may be stored in their containers until required for use. Mesh or other air-permeable screen-type material permits inhalation through the removable filter element, while a one-way valve permits exhalation. The filter element may be removed from a flexible gasket-type mount in the shell without the need for removing the mask. This may be helpful in some fire situations where removal of the mask would require removal of goggles or helmet and thereby expose the wearer to additional risks.
The resulting filter mask of any of the aforementioned embodiments presents significant improvements over the prior art. Further benefits will be readily appreciated by those skilled in the art with reference to the drawings and the written description of the preferred embodiments set forth below.